JP2012098594A - Imaging apparatus and imaging method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the AF range scan time by accurately reflecting an imaging intention of a user in a high speed continuous imaging.SOLUTION: The imaging apparatus includes: imaging means; image display means for displaying an image imaged by the imaging means; position specification receiving means arranged on a display surface of the image display means for receiving the position specification of the user for the displayed image; lens moving means for moving the lens within the range of focus; evaluation value calculation means for calculating an evaluation value indicating the degree of sharpness of the image which is calculated from an image signal outputted by the imaging means regarding the range including a plurality of positions which the user had the positions specified at once through the position specification receiving means for respective lens positions which are moved by the lens moving means; focal position determination means for determining a focal position based on the calculated evaluation value; and control means for high speed continuous imaging for carrying out imaging at high speed at a plurality of focal positions determined by the focal position determination means.

Description

  The present invention relates to an imaging apparatus and an imaging method that perform high-speed continuous shooting at a plurality of in-focus positions.

  Conventionally, as a type of autofocus function of an imaging device, the camera automatically determines a plurality of in-focus positions from subject information, performs high-speed continuous shooting while moving the focus to each distance, By storing the result as a multi-picture format file, there is a function that enables the user to select an image focused on a desired area after shooting (for example, Patent Document 1). Such a function is called a “multi-target AF” function by the applicant of the present invention and is installed in some products. This function is effective when shooting a scene having many desired in-focus positions in the screen, such as close-up of a flower.

  In this multi-target AF function, an AF ranging scan operation is performed before high-speed continuous shooting in order to determine a plurality of in-focus positions. In this AF distance scanning operation, an AF evaluation value is acquired from an image captured while moving the focus lens to the entire movable range of the focus lens, the peak position is sequentially selected, and the in-focus position is determined. Is going.

  Further, as a conventional technique, Patent Document 2 discloses an imaging apparatus that can accurately specify a subject to be focused by determining an autofocus area based on a line designated by a photographer on a screen. It is disclosed.

  Further, in Patent Document 3, the AF distance scanning operation requires a processing time to acquire an AF evaluation value while sequentially moving the focus lens to the entire range in which the focus lens can move and sequentially select the peak position. For this reason, an imaging apparatus that employs an evaluation value scanning operation (such as a contrast AF operation) that has been specially speeded up is disclosed.

  However, the AF distance scanning operation up to now (for example, in Patent Document 1) always acquires AF evaluation values while moving the focus lens to the entire movable range of the focus lens, and sequentially selects and matches the peak position. Although the focus position is determined, the camera sometimes selects a focus position that is not intended by the user. As a result, a plurality of focus positions including a focus position that is not intended by the user are selected. The camera sometimes decided automatically. As a result, there is a problem that it is impossible to focus on a subject that accurately reflects the user's intention to shoot. Also, since the AF ranging scan operation processing time is always AF throughout the entire area, regardless of the user's intention to shoot, the processing time cannot be reduced because it is always a certain time, and depending on the subject There was a problem of missing a photo opportunity during continuous shooting.

  On the other hand, the imaging device disclosed in Patent Document 2 can focus on a subject that accurately reflects the user's intention to shoot, but there is a problem that the AF distance scanning time is shortened and a photo opportunity is not missed. It has not been solved. In addition, although the imaging apparatus disclosed in Patent Document 3 speeds up the evaluation value scanning operation, it is difficult to say that the high-speed continuous shooting reflecting the user's shooting intention and the optimum continuous shooting number are realized.

  The present invention has been made in view of the above, and at the time of high-speed continuous shooting, it is possible to perform focusing that accurately reflects the user's shooting intention and to obtain an optimum number of continuous shots, and as a result, high-speed continuous shooting. An object of the present invention is to provide an imaging apparatus and an imaging method capable of reducing the AF distance scanning time to be performed before imaging.

  In order to solve the above-described problems and achieve the object, an imaging apparatus according to the present invention includes an imaging unit that converts a subject image into an electrical signal via a lens, and an image display unit that displays an image captured by the imaging unit. A position designation receiving unit that is installed on a display surface of the image display unit and receives a user position designation with respect to an image displayed on the image display unit, and a lens moving unit that moves the lens within a focus adjustment range. For each lens position moved by the lens moving means, a range including a plurality of positions designated at once by the user via the position designation receiving means is calculated from the image signal output from the imaging means. An evaluation value calculation unit that calculates an evaluation value indicating the sharpness of the image, and a focus position that determines a focus position based on the evaluation value calculated by the evaluation value calculation unit A constant section, for a given target distance range, characterized in that it comprises a high-speed continuous photographing control means for performing high-speed photography in said plurality of focus positions determined by the focus position determination unit.

  The imaging method of the present invention is installed on an imaging means for converting a subject image into an electrical signal via a lens, an image display means for displaying an image captured by the imaging means, and a display surface of the image display means. An imaging apparatus comprising: a position designation receiving means for accepting a user's position designation with respect to an image displayed on the image display means; and a lens moving means for moving the lens within a focus adjustment range. The control means for controlling, as the evaluation value calculating means, for each lens position moved by the lens moving means, the imaging for a range including a plurality of positions designated at a time by the user via the position designation accepting means An evaluation value indicating the sharpness of the image calculated from the image signal output from the means is calculated, and calculated by the evaluation value calculation means as the focus position determination means In-focus position is determined based on the evaluated value, and high-speed continuous shooting control means performs high-speed shooting at the plurality of focus positions determined by the focus position determination means for a predetermined target distance range. It is characterized by.

  According to the present invention, during high-speed continuous shooting, focusing that accurately reflects the user's shooting intention can be performed, and further, the AF distance scanning time to be performed before high-speed continuous shooting can be shortened, so that a shutter chance can be obtained. It has the effect of not missing.

FIG. 1 is a perspective view illustrating a front surface and an upper surface of a digital camera according to an embodiment. FIG. 2 is a perspective view showing a top surface and a back surface of the digital camera shown in FIG. FIG. 3 is a perspective view showing a front surface and a lower surface of the digital camera. FIG. 4 is a diagram illustrating a configuration example of a control system inside the digital camera. FIG. 5 is a block diagram showing a main part characteristic in the embodiment of the control program executed by the CPU. FIG. 6 is a diagram illustrating an example of the situation of the subject and the positional relationship. FIG. 7 shows a case in which an evaluation value scan is performed with respect to a focus position from the shortest shooting distance to infinity on the shooting distance that is the entire range of the distance range that can be shot, that is, the entire focus area on the screen. It is the figure which added and showed the change curve of the highest evaluation value in several areas of simulation. FIG. 8 is a flowchart for explaining the multi-target AF process. FIG. 9 is a diagram illustrating types of general gesture operations. FIG. 10 is a diagram illustrating an example of an operation method using a known tap. FIG. 11 is a diagram illustrating an example of a gesture operation for designating a subject position in the embodiment.

  Hereinafter, a digital camera which is an embodiment of an imaging apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

(Outline of the embodiment)
The imaging apparatus and imaging method of the present embodiment adopt an evaluation value scanning operation of multi-target AF (in this specification, autofocus is described as “AF”), and have the following characteristics.

  In short, in an imaging device having a touch panel on the display surface of the image monitor, a first subject to be focused is determined by the first touch operation, and then the first subject to be focused on the locus of the drag operation by the drag operation. The other subject to be focused is determined so as to include other subjects, and finally, the last one subject to be focused is determined by the detach operation, so that the selection of the subject position at a plurality of points is performed once. The feature is that it can be done by gesture operation.

(Configuration of digital camera according to one embodiment)
FIG. 1 is a perspective view illustrating a front surface and an upper surface of a digital camera according to an embodiment. 2 is a perspective view showing an upper surface and a rear surface of the digital camera shown in FIG. 1, and FIG. 3 is a perspective view showing a front surface and a lower surface of the digital camera.

  A digital camera 30 shown in the figure is an imaging device that receives light passing through a lens by a solid-state imaging device, converts an analog signal that is an output of the solid-state imaging device into a digital signal, and records the digital signal on a memory card.

  On the front and top surfaces of the digital camera 30, as with a general digital camera, a POWER (power) button 1, shutter button 2, flash light emitting unit 3, AF auxiliary light / self-timer lamp 4, lens cover 5, microphone 6, a speaker 7 and a lens 8 are arranged.

  As shown in FIG. 2, on the back of the digital camera 30, an image monitor 9, a zoom lever (telephoto / wide angle) 10, a mode switch 11, a playback button 12, an ADJ. Button 13, delete / self-timer button 14, ↑ / MODE button 15, → / quick review button 16, MENU / OK button 17, ↓ / macro button 18, ← / flash button 19, DISP. A button 20, an AV output terminal 21, and a USB terminal 22 are arranged. Also, a tripod screw hole 23 and a battery / card cover 24 are arranged on the lower surface of the digital camera 30 as shown in FIG.

  When the battery / card cover 24 is opened, a battery insertion portion and a card insertion portion (both not shown) are provided, and a battery and a memory card are loaded therein.

  The mode switch 11 is composed of a two-position slide switch, and the mode of the digital camera 30 can be set according to the position. Camera operations such as still image shooting and moving image shooting are performed after the mode switch 11 is switched. There are two types of modes of the digital camera 30: a “scene mode” and a “still image shooting mode”.

  The “still image shooting mode” is used when shooting a still image. "Scene mode" is a "portrait mode" suitable for portrait shooting, "face mode" for face recognition and adjustment suitable for face shooting, "sport mode" suitable for shooting fast-moving subjects, “Distant view mode” for infinite focus, “night view mode” suitable for night scene shooting, “high sensitivity mode” for easy composition determination during night scene shooting, and macro shooting of large subjects using digital zoom "Zoom Macro Mode" that can capture images, "Monochrome Mode" that captures images in black and white, "Sepia Mode" that captures images in sepia, and when shooting a square subject from an oblique direction, the captured image is captured from the front Various shooting modes, such as “oblique correction mode” for correcting images, “character mode” for shooting characters, and “movie shooting mode” for shooting movies. Including soil.

  The playback button 12 functions as a button for instructing the mode of the digital camera 30 to “playback mode”. When this button is pressed in the shooting mode (“still image shooting mode” or “scene mode”), the playback mode is set and the last still image is displayed on the image monitor 9.

  The lens 8 is constituted by a retractable zoom lens. When the camera is turned on by the POWER button 1 and the mode of the camera is set to the photographing mode by the mode switch 11, the digital camera 30 It is paid out.

  A zoom lever (telephoto / wide angle) 10 is a three-position lever disposed around the shutter button 2 and functions as a means for instructing the zoom of the lens 8. When the digital camera 30 operates the zoom lever (telephoto / wide angle) 10 in the shooting mode to the telephoto side, the lens 8 zooms to the telephoto side, and operates the zoom lever (telephoto / wide angle) 10 to the wide angle side. Then, the lens 8 performs zooming to the wide angle side, and changes the focal length of the lens 8. On the other hand, when the zoom lever (telephoto / wide angle) 10 is operated to the wide angle side in the playback mode, the image being reproduced is reduced and displayed, and when the zoom lever (telephoto / wide angle) 10 is operated to the telephoto side, the image being reproduced is displayed. The display magnification of the enlarged and reproduced image is changed.

  The shutter button 2 is composed of a two-stage switch and can be operated halfway and fully. In the digital camera 30, the AE (automatic exposure) / AF (autofocus) function is activated by half-pressing the shutter button 2, and the AWB (auto white balance) function is activated by performing the push-off operation to execute shooting.

  The image monitor 9 is composed of a liquid crystal display capable of color display and a touch panel, and is used as an image display panel for displaying a photographed image in the reproduction mode, and a user interface for performing various setting operations. Used as a display panel. In the shooting mode, a live view is displayed as necessary and used as a view angle confirmation finder.

  ADJ. The button 13 is a button that can perform exposure, white balance, and ISO switching independently. The delete / self-timer button 14 is used to delete a file during reproduction and to activate the self-timer during shooting.

  The ↑ / MODE button 15, the → / quick review button 16, the ↓ / macro button 18, and the ← / flash button 19 function as direction instruction means for inputting instructions in four directions, up, down, left, and right. Used for selection etc. The ↑ / MODE button 15 is also used when performing a predetermined setting. The → / quick review button 16 is also used when a captured image is displayed on the image monitor 9 without switching to the playback mode. The ↓ / macro button 18 and the ← / flash button 19 are also used for switching the macro function and the flash function, respectively.

  The MENU / OK button 17 functions as a button (MENU button) for instructing transition from the normal screen to the menu screen in each mode, and also functions as a button (OK button) for instructing selection confirmation, execution of processing, and the like. To do.

  DISP. The button 20 functions as a button for instructing to change the display state of the screen, such as switching between display / non-display of the mark on the image monitor 9. Each time this button is pressed in the shooting mode, the display is switched as follows: histogram display → grid guide display → no display → image monitor off → normal mark display → histogram display →. Each time this button is pressed in the playback mode, the display is switched from histogram display → highlight display → no display → normal mark display → histogram display →. This button also functions as a button for instructing to cancel the input operation or return to the previous operation state.

  FIG. 4 is a diagram illustrating a configuration example of a control system inside the digital camera 30.

  The overall operation of the digital camera 30 is comprehensively controlled by a central processing unit (CPU 40). The CPU 40 includes an operation unit 41 (POWER (power) button 1, shutter button 2, zoom lever (telephoto / wide angle) 10, mode switch 11, playback button 12, ADJ. Button 13, delete / self-timer button 14, ↑ / Digital camera 30 according to a predetermined control program based on operation signals input from MODE button 15, → / quick review button 16, MENU / OK button 17, ↓ / macro button 18, ← / flash button 19, DISP. Button 20). Overall control. Power is supplied to the CPU 40 from the battery 25, and power converted into a voltage by the DC / DC converter 53 is supplied to each circuit constituting the digital camera 30.

  A flash ROM 58 connected to the CPU 40 via the bus stores a digital camera 30 that stores a control program 90 executed by the CPU 40, various data necessary for control, user setting information, and the like (for example, camera adjustment data 91 and camera setting data 92). Stores various setting information related to the operation of.

  The memory (SDRAM 54) is used as a temporary storage area for calculation work areas of the CPU 40, image data (Raw-RGB image data 55, YUV image data 56, compression / expansion image data 57), and the like.

  The lens barrel unit 100 controls a zoom lens 81 that captures an optical image of a subject, a focus lens 82, a lens driving unit 86 that controls them, an aperture 83, an aperture driving unit 87 that controls the aperture 83, a mechanical shutter 84, and a mechanical shutter 84. A shutter driving unit 88 is included.

  The lens driving unit 86, the aperture driving unit 87, and the shutter driving unit 88 are driven and controlled by a driving command from the CPU 40.

  When the power of the digital camera 30 is turned on, the control program 90 is loaded into the memory (SDRAM 54), and the CPU 40 controls the operation of each part of the apparatus according to the control program 90. At the same time, data and the like necessary for control are temporarily stored in the memory (SDRAM 54).

  Since the flash ROM 58 is a rewritable semi-nonvolatile memory, the control program 90, various data necessary for control, and user setting information can be changed, and the function can be easily upgraded.

  The digital camera 30 is set to the shooting mode by setting the mode switch 11 of the operation unit 41 to the shooting position, and shooting is possible. Then, when the shooting mode is set, the lens 8 is extended to enter a shooting standby state.

  Under this photographing mode, the subject light that has passed through the lens 8 forms an image on the light receiving surface of the solid-state imaging device via the diaphragm 83.

  The solid-state imaging device is composed of a CCD 85, and on its light receiving surface, red (R), green (G), and blue (B) color filters arranged in a predetermined arrangement structure (Bayer, G stripe, etc.). A number of photodiodes (light receiving elements) are two-dimensionally arranged via

  The subject light that has passed through the lens 8 is received by each photodiode and converted into a signal charge in an amount corresponding to the amount of incident light.

  The signal charge accumulated in each photodiode is sequentially read out as a voltage signal (image signal) corresponding to the signal charge based on the drive pulse supplied from the timing generator (TG89) and is read to the analog processing unit (CDS / AMP42). Added.

  The analog processing unit (CDS / AMP42) samples and holds the input RGB signal for each pixel (correlated double sampling processing), amplifies it, and outputs it to the A / D converter 43.

  The A / D converter 43 converts the analog RGB signal output from the analog processing unit (CDS / AMP 42) into a digital RGB signal, and outputs the digital RGB signal. The digital RGB signal output from the A / D converter 43 is Then, it is taken into the memory (SDRAM 54) as Raw-RGB image data 55 via the sensor input control unit 44.

  The image signal processing unit 46 processes the Raw-RGB image data 55 captured in the memory 54 in accordance with a command from the CPU 40, converts it into a luminance signal (Y signal) and a color difference signal (Cr, Cb signal), and YUV image data 56. Is generated.

  That is, the image signal processing unit 46 includes a synchronization circuit (a processing circuit that converts a color signal into a simultaneous expression by interpolating a spatial shift of the color signal associated with the color filter array of the single CCD), and a white balance correction circuit. Functions as an image processing means including a gamma correction circuit, a contour correction circuit, a luminance / color difference signal generation circuit, and the like. And a color difference signal (luminance / color difference signal). The generated luminance / color difference signal is stored in the memory (SDRAM 54) as YUV image data 56.

  When outputting a captured image to the image monitor 9, YUV image data 56 is sent from the memory (SDRAM 54) to the OSDMIX unit 48.

  The OSDMIX unit 48 combines the luminance / color difference signals of the input YUV image data 56 by superimposing on-screen display data such as characters and graphics, and outputs them to the video encoder 65 and the image monitor signal processing unit 49. As a result, required shooting information and the like are displayed superimposed on the image data.

  The video encoder 65 converts the luminance / color difference signal of the input YUV image data 56 into a display digital display output signal (for example, NTSC color composite video signal), and the D / A converter 66 performs digital display output. Convert the signal to an analog video output signal.

  The video AMP 67 performs 75Ω impedance conversion on the analog video signal output from the D / A converter 66 and outputs the analog video signal to the AV output terminal 21 for connection to an external display device such as a television. As a result, the image captured by the CCD 85 is displayed on an external display device such as a television.

  On the other hand, the image monitor signal processing unit 49 converts the luminance / color difference signal of the input YUV image data 56 into an RGB signal which is an input signal format of the image monitor 9 and outputs the RGB signal to the image monitor 9. As a result, the image captured by the CCD 85 is displayed on the image monitor 9.

  The image signal is periodically taken from the CCD 85, the YUV image data 56 in the memory (SDRAM 54) is periodically rewritten by the luminance / color difference signal generated from the image signal, and output to the image monitor 9 and the AV output terminal 21. Thus, an image captured by the CCD 85 is displayed in real time. The photographer can confirm the shooting angle of view by viewing the image (live view) displayed in real time on the image monitor 9.

  Shooting is performed by pressing the shutter button 2. Prior to shooting, when the photographer needs to adjust the angle of view, the photographer operates the zoom lever (telephoto / wide angle) 10 to zoom the zoom lens 81 and adjust the angle of view.

  When the shutter button 2 is half-pressed, an R1 ON signal is input to the CPU 40, and the CPU 40 performs AE / AF processing.

  First, an image signal captured from the CCD 85 via the sensor input control unit 44 is input to the AF detection unit 51 and the AE / AWB detection unit 52.

  The AE / AWB detection unit 52 includes a circuit that divides one screen into a plurality of areas (for example, 16 × 16) and integrates R, G, and B signals for each divided area, and provides the integrated value to the CPU 40. .

  The CPU 40 detects the brightness of the subject (subject brightness) based on the integrated value obtained from the AE / AWB detection unit 52, and calculates an exposure value (shooting EV value) suitable for shooting. Then, an aperture value and a shutter speed are determined from the obtained photographing EV value and a predetermined program diagram, and an appropriate exposure amount is obtained by controlling the electronic shutter and the aperture drive unit 87 of the CCD 85 according to the determined aperture value and shutter speed.

  Further, the AE / AWB detection unit 52 calculates an average integrated value for each color of the R, G, and B signals for each divided area during automatic white balance adjustment, and provides the calculation result to the CPU 40. The CPU 40 obtains the ratio of R / G and B / G for each divided area from the obtained R accumulated value, B accumulated value, and G accumulated value, and obtains the calculated R / G and B / G values. The light source type is determined based on the distribution in the color space of R / G and B / G.

  Then, according to the white balance adjustment value suitable for the discriminated light source type, for example, the value of each ratio is approximately 1 (that is, the RGB integration ratio is R: G: B≈1: 1: 1 on one screen). As described above, the gain value (white balance correction value) for the R, G, and B signals of the white balance adjustment circuit is controlled to correct the signal of each color channel.

  The AF detection unit 51 includes a high-pass filter that passes only a high-frequency component of the G signal, an absolute value processing unit, an AF area extraction unit that extracts a signal within a predetermined focus area (for example, the center of the screen or a specified area), and The CPU 40 is notified of the integrated value data obtained by the AF detection unit 51. The integrated value data is obtained by integrating the absolute value data in the AF area. The CPU 40 calculates a focus evaluation value (AF evaluation value) at a plurality of AF detection points while controlling the lens driving unit 86 to move the focus lens 82, and a lens position where the evaluation value is maximized is set as a focus position. decide. Then, the lens driving unit 86 is controlled so that the focus lens 82 moves to the obtained in-focus position.

  As described above, the AE / AF processing is performed by half-pressing the shutter button 2.

  Thereafter, when the photographer presses down the shutter button 2, an R2 ON signal is input to the CPU 40, and the CPU 40 starts photographing and recording processing. That is, the CPU 40 controls the aperture driving unit 87 to move the aperture 83 according to the aperture value determined based on the photometric result, and controls the shutter driving unit 88 to control the opening / closing operation of the mechanical shutter 84 according to the shutter speed value. The CCD 85 is exposed by controlling the exposure time of the CCD 85.

  The image signal output from the CCD 85 is taken into the memory (SDRAM 54) via the analog processing unit (CDS / AMP) 42, the A / D converter 43, and the sensor input control unit 44, and the luminance / After being converted into a color difference signal, it is stored as YUV image data 56 in a memory (SDRAM 54).

  The YUV image data 56 stored in the memory (SDRAM 54) is added to the compression / decompression processing unit 47, compressed in accordance with a predetermined compression format (for example, JPEG format), and then again compressed and decompressed image data 57 in the memory (SDRAM 54). After being stored and made into an image file of a predetermined image recording format (for example, Exif format), it is recorded on a memory card 29 (for example, an SD card) via the card control unit 50.

  The image recorded in the memory card 29 as described above can be reproduced and displayed on the image monitor 9 by pressing the reproduction button 12 of the operation unit 41.

  When the playback button 12 is pressed and the mode of the digital camera 30 is set to the playback mode, the CPU 40 outputs a command to the card control unit 50 and causes the memory card 29 to read out the last image file recorded.

  The compressed image data of the read image file is added to the compression / expansion processing unit 47 and expanded to an uncompressed luminance / color difference signal, and then the image monitor 9 is passed through the OSDMIX unit 48 and the image monitor signal processing unit 49. Is output. As a result, the image recorded on the memory card 29 is reproduced and displayed on the image monitor 9.

  In order to perform USB communication with an external device such as a personal computer, connection is made via the USB terminal 22, and the CPU 40 controls the USB control unit 59 to perform USB communication.

  Audio signal data such as shutter sound and operation sound is stored in the flash ROM 58, and the CPU 40 controls the audio signal processing unit 45 and outputs the audio data to the audio CODEC 61 via the audio signal processing unit 45.

  The audio CODEC 61 incorporates a microphone amplifier that amplifies the input audio signal and an audio amplifier for driving the speaker 7. The audio CODEC 61 includes a microphone 6 for inputting a sound signal by the photographer, and an audio signal. Is connected, so that an audio signal is output from the speaker 7.

(Control program configuration)
FIG. 5 shows a main part characteristic of the present embodiment in the control program 90 executed by the CPU 40. This control program includes an AF ranging scan unit 401, a position detection unit 402, a locus analysis unit 403, and a high-speed continuous shooting control unit 404.

  The AF distance scanning unit 401 calculates the AF evaluation values at all the AF detection points on the screen while moving the focus lens 82 by controlling the lens driving unit 86 before high-speed continuous shooting, and the evaluation value is the maximum. A plurality of lens positions are obtained, and an evaluation value scanning process for determining the in-focus position is performed.

  The position detection unit 402 detects the position designated by the photographer (user) via the touch panel (position designation receiving means) with respect to the live view displayed on the image monitor 9.

  The trajectory analysis unit 403 analyzes the trajectory from the start point to the end point of the position specified by the photographer detected by the position detection unit 402, acquires a plurality of positions included from the start point to the end point, and the AF distance scanning unit In 401, an AF detection point to be used is set.

  The high-speed continuous shooting control unit 404 performs high-speed continuous shooting while moving the focus to the in-focus position determined by the AF distance scanning unit 401, and performs control to save the result as a multi-picture format file. Further, the high-speed continuous shooting control unit 404 includes a frame indicating a focus area in which a focus position is determined by the AF distance scanning unit 401 in a range including a plurality of positions designated by the user at a time via the touch panel. AF frame) is displayed on the imaging screen displayed on the image monitor 9. Then, when any of the displayed AF frames is tapped or touched via the touch panel, high-speed continuous shooting is started (see FIG. 11 described later).

  In order for the position detector 402 to detect the position indicated by the photographer using a finger or a pen tip with respect to the live view displayed on the image monitor 9, a touch panel (other transparent contact) provided to the image monitor 9 is used. It may be an expression position detecting means). Examples of the transparent contact type position detecting means include a resistive film method, a surface acoustic wave method, an acoustic pulse recognition method, an electromagnetic induction method, and the like. Among them, the electromagnetic induction method is a method capable of detecting the pressing strength when the image monitor 9 is pointed with a finger or a pen tip.

(Multi target AF function)
In the following, the multi-target AF function by the AF ranging scan unit 401 will be described with reference to FIGS. 6 and 7.

  FIG. 6 shows an example of the situation of the subject and the positional relationship. At the closest distance, there is a rock 601 on the right side and two persons 602 and 603 behind it. The person 602 is closer than the person 603 and on the right side of the person 603. Further, there is a mountain 604 behind the persons 602 and 603, and this mountain 604 is the farthest distance.

  FIG. 7 shows a case in which an evaluation value scan is performed with respect to a focus position from the shortest shooting distance to infinity on the shooting distance that is the entire range of the distance range that can be shot, that is, the entire focus area on the screen. The change curve of the highest evaluation value in a plurality of areas is shown in a simulated manner. The horizontal axis is the shooting distance, the left end is the infinite focus position, and the vertical axis is the evaluation value. The “evaluation value” (AF evaluation value) here is a value calculated by extracting a high-frequency component from an imaging component or an imaging signal, and is a value indicating the sharpness or contrast of the image.

  In the example of the image shown in FIG. 6, the evaluation value curve has a peak as shown in FIG. In this example, the closest person 602 has the highest evaluation value, and the evaluation values decrease in the order of the rock 601 as the closest subject, the mountain 604 in the distant view, and the distant person 603 in this order. However, the peak of the evaluation value curve of each subject is higher than a threshold necessary for focusing (hereinafter referred to as “focus threshold”), and any subject can be focused. Under conditions.

  In the normal shooting mode, it is determined from the relationship between the position of the focus lens and the evaluation value that the subject at the closest position having a peak equal to or greater than the focusing threshold, and thus the rock 601 in the above example, is the closest subject. , Focus on this and shoot.

(Details of multi-target AF function)
FIG. 8 is a flowchart for explaining the multi-target AF process.

  In the multi-target AF mode, AF by the multi-target AF function is performed. In this mode, the AE process is first performed by half-pressing the shutter button 2 (step S101), and then the above-described evaluation value scanning process by the AF distance scanning unit 401 is performed (step S102).

  The evaluation value scan in the evaluation value scanning process is performed from the short distance side (in this embodiment, the position where the focus lens 82 is extended to the most object side) toward the infinity side. That is, the movement of the focus lens 82 is started from the standby position of the focus lens 82, and the evaluation value scan is started from the focus lens position that can focus on the subject at the shortest shooting distance. At this time, the direction of the evaluation value scan, the standby position before the evaluation value scan, and the like are appropriately set optimally according to various design circumstances. The evaluation value scan is performed by calculating the evaluation value while imaging the subject. After the evaluation value scan is started, imaging data is acquired while moving the lens in minute steps, an evaluation value is calculated, and the evaluation value is determined.

  Next, it is determined whether or not there is an in-focus position at which the evaluation value calculated by the evaluation value scan is equal to or greater than the in-focus threshold (step S103). In the example shown in FIGS. 6 and 7, since there is a focus position at which the evaluation value is equal to or greater than the focus threshold, if the calculated evaluation value exceeds the focus threshold (predetermined threshold) (Yes in step S103) The focus lens remains at the current position at the determined in-focus position (step S104), and the evaluation value scanning operation ends. As a camera operation, the shooting start position of the focus lens is determined here, and the camera is in a state of waiting for a shutter button push-off operation.

  In this case, the rock 601, two persons 602 and 603 behind the rock 601, and a mountain 604 behind the persons 602 and 603 are determined to be in focus. After that, four image files focused on each subject are obtained by performing continuous shooting while moving the focus position so that each subject is in focus by pressing the shutter button.

  On the other hand, when the calculated evaluation value is less than the focusing threshold (predetermined threshold) (that is, when the presence of the subject cannot be confirmed) (No in step S103), the imaging apparatus is focused as in the conventional case. The focus lens is moved to the shortest possible shooting distance (step S105). After that, when the shutter button is fully pressed, the entire shooting distance range from the position to the position where the infinite focus is achieved is shot at a predetermined interval.

  As described above, in multi-target AF, the camera automatically determines a plurality of in-focus positions. As a user's intention, the rock 601 may be an unintended subject, but in the above-described method, it is a shooting target. In order to exclude the rock 601 from the target, it is necessary to limit the evaluation value scan range.

(Gesture operation with touch panel)
In this embodiment, in order to specify the subject, a plurality of subjects are specified by a user instruction from the touch panel provided in the image monitor 9. Hereinafter, general types of gesture operations are shown (see FIG. 9).

(A) Tap: An operation of tapping the touch panel with a finger. Equivalent to mouse click.
(B) Press and hold: An operation of pressing and holding one place on the touch panel with a finger. Equivalent to right mouse click.
(C) Drag: An operation of shifting a finger while keeping the finger in contact with the touch panel.

(Photographing with known technology)
In order to specify a single subject, it is known (for example, JP 2009-239733 A) that a subject can be easily specified by tapping the target subject on the screen. The operation method in this case is shown in FIG. In the case of FIG. 10, it is assumed that the target subject is a person, and the positional relationship between the four persons A to D is different.

  First, when the user wants to focus on the person A and taps the person A, the AF frame 1 for feeding back the selection result to the user is displayed (FIG. 10A).

  Further, since the user wants to focus on the person C, when the user taps the person C, the AF frame 2 for feeding back the selection result to the user is displayed (FIG. 10B).

  Since the user has selected all the persons he / she wants to focus on, the user performs shooting next. In this example, there are two types of shooting, and as shown in (c-1) of FIG. 8, the shutter button is pressed and shooting is performed, or as shown in (c-2), the displayed AF frame 1 or Shooting is performed by tapping or touching any of the AF frames 2.

  In order to specify a plurality of subjects in the order intended by the user, when only a tap operation is performed, it is necessary to input a plurality of times by a plurality of taps, which takes time for input. Further, if there is an input mistake during input, it is necessary to provide an interface for determining which input point to cancel again, which complicates the operation. For example, when a context menu is used as an interface for instructing which input point to cancel, for example, when a press and hold (see FIG. 9B) is performed, the context menu is displayed. Although the cancel operation is started, the operation is obviously complicated for the user.

  Therefore, in the present embodiment, by the touch and drag operation, the first focus start position is determined by the first touch operation, and subsequently, on the locus of the drag operation by the drag operation, other than the first focus designated position. A plurality of in-focus designated positions are determined so as to include the positions, and finally the last in-focus designated position is determined by a detach operation. As described above, the selection (designation) of a plurality of subject positions can be performed by one gesture operation, thereby eliminating the complexity of the operation. Then, in the evaluation value scan processing in step S102 described above with reference to FIG. 8, the evaluation value scan is performed not on the entire area as in the prior art but on a plurality of in-focus designated positions designated by the drag operation.

  Here, FIG. 11 shows an example of a gesture operation for designating a subject position in the present embodiment. In the example shown in FIG. 11, as in the example described above with reference to FIG. 10, the target subject is a person, and the positional relationship between the four persons A to D is different.

  First, when the user wants to focus on the person A and touches the person A, the AF frame 1 for feeding back the selection result to the user is displayed (FIG. 11A).

  Furthermore, since the user wants to focus on the persons B, C, and D, when the user drags in the order of the persons B, C, and D (FIG. 11B), AF frames 2 to 4 for feeding back the selection result to the user are displayed. (FIG. 11C).

  Since the user has selected all the persons he / she wants to focus on, the user performs shooting next. In the example of FIG. 11, as shown in FIG. 11D, shooting is performed by tapping or touching any of the displayed AF frames 1 to 4. Of course, you can press the shutter button and take a picture. The drag operation for designating the subject position in the present embodiment can be arbitrarily performed, and the drag operation can be performed in a curved line shape, a straight line shape, or a circular shape or an elliptical shape in which the start point and the end point coincide with each other. .

  As described above, in the conventional multi-target AF described above, it is necessary to calculate the AF evaluation value for all the focus areas and obtain the lens position at which the evaluation value is maximized. Since the target subject position is specified, only a specific focus area needs to be calculated. As a result, the AF evaluation value calculation time can be shortened, and as a result, AF distance scanning operation before high-speed continuous shooting Time can be shortened.

  In addition, since it is only necessary to calculate a specific focus area, the lens position where the evaluation value is maximum in the corresponding focus area is focused on all positions with respect to the focus position from the shortest shooting distance to infinity on the shooting distance. Since it is not necessary to move the lens, the AF distance scanning operation time before high-speed continuous shooting can be shortened as a result. Further, since the AF distance scanning operation time can be shortened, there is an effect that a photo opportunity is not missed.

  In addition, since high-speed continuous shooting at a focus position in a specific focus area may be performed, images unnecessary for the user are eliminated, and as a result, the number of continuous shots can be optimized.

DESCRIPTION OF SYMBOLS 1 POWER (power) button 2 Shutter button 3 Flash light emission part 4 AF auxiliary light / self-timer lamp 5 Lens cover 6 Microphone 7 Speaker 8 Lens 9 Image monitor (image display means)
30 Digital camera 40 CPU
41 Operation section 42 CDS / AMP
43 A / D converter 44 Sensor input control unit 51 AF detection unit 52 AE / AWB detection unit 81 Zoom lens 82 Focus lens 83 Aperture 84 Mechanical shutter 85 CCD (Imaging means)
86 Lens drive unit (lens moving means)
87 Aperture drive unit 88 Shutter drive unit 401 AF distance measurement scan unit (evaluation value calculation means, focus position determination means)
402 Position Detection Unit 403 Trajectory Analysis Unit 404 High-Speed Continuous Shooting Control Unit (High-Speed Continuous Shooting Control Unit)

JP 2005-277813 A JP 2010-128395 A JP 2009-042621 A

Claims (7)

Imaging means for converting a subject image into an electrical signal via a lens;
Image display means for displaying an image captured by the imaging means;
A position designation receiving unit that is installed on a display surface of the image display unit and receives a user position designation with respect to an image displayed on the image display unit;
Lens moving means for moving the lens within a focus adjustment range;
For each lens position moved by the lens moving means, an image calculated from an image signal output from the imaging means for a range including a plurality of positions designated at once by the user via the position designation receiving means. Evaluation value calculation means for calculating an evaluation value indicating the sharpness of
A focus position determining means for determining a focus position based on the evaluation value calculated by the evaluation value calculating means;
An image pickup apparatus comprising: high-speed continuous shooting control means that performs high-speed shooting at the plurality of focus positions determined by the focus position determination means for a predetermined target distance range.   The imaging apparatus according to claim 1, wherein a plurality of position designations are received at a time by a touch and drag operation performed on the position designation receiving unit.   When receiving a position designation by the touch and drag operation, a first position is determined by the first touch operation, and a plurality of positions other than the first position are included on the trajectory of the drag operation by the subsequent drag operation. The imaging apparatus according to claim 2, wherein a position is determined, and finally the last position is determined by a detach operation.   The high-speed continuous shooting control unit is configured to select a focus area in which a focus position is determined by the focus position determination unit in a range including a plurality of positions specified by the user at a time via the position specification reception unit. The imaging apparatus according to claim 1, wherein a frame to be displayed is displayed on an imaging screen displayed on the image display unit.   The high-speed continuous shooting control unit starts the shooting by touching the frame indicating the focus area displayed on the image display unit via the position designation receiving unit. 5. The imaging device according to 4.   The imaging apparatus according to claim 1, wherein the position designation receiving unit is a touch panel. An image pickup unit that converts a subject image into an electrical signal through a lens, an image display unit that displays an image picked up by the image pickup unit, and a display surface of the image display unit, and is displayed on the image display unit Control means for controlling the imaging device with respect to an imaging device comprising: a position designation receiving unit that receives a user position designation with respect to an image; and a lens moving unit that moves the lens within a range of focus adjustment.
As an evaluation value calculation means, for each lens position moved by the lens moving means, an image output from the imaging means for a range including a plurality of positions designated by the user at once via the position designation receiving means Calculate an evaluation value indicating the sharpness of the image calculated from the signal,
As a focus position determination means, a focus position is determined based on the evaluation value calculated by the evaluation value calculation means,
An imaging method characterized in that, as high-speed continuous imaging control means, imaging is performed at a high speed for the predetermined target distance range at the plurality of in-focus positions determined by the in-focus position determining means.

Images